This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Polycystic Ovary Syndrome (PCOS) affects 5-10% of women of reproductive age. Recent evidence strongly suggests that there is a genetic defect in insulin action in many PCOS women. This condition may predispose females and other family members to an increased risk for diabetes and heart disease. It is the overall hypothesis of this research that a substantial amount of PCOS and the insulin resistance associated with it has a genetic basis and that there is a male as well as a female phenotype. The purpose of this study is to determine the clinical and biochemical reproductive phenotype in members of PCOS kindreds for subsequent genetic linkage analysis. We will also attempt to determine whether a male, a premenarchal and/or a post-menopausal phenotype exists in familial PCOS.